The present disclosure relates to touch panel devices.
Recently, a technique called force feedback has been proposed in which feeling of pressing an operation key is fed back as tactile feeling to the operator in touch panel devices including a touch panel arranged on a display. Some touch panel devices, which is provided with a touch panel including piezoelectric elements, feed back tactile feeling to an operator in a manner that drive signals are applied to the piezoelectric elements to vibrate the touch panel upon operator's touch with the operation surface of the touch panel.